METHOD OF MEASURING EDDY-CURRENT TYPE NONMAGNETIC METAL FILM THICKNESS, AND APPARATUS FOR MEASURING EDDY-CURRENT TYPE NONMAGNETIC METAL FILM THICKNESS FOR PERFORMING THE METHOD

摘要

PROBLEM TO BE SOLVED: To provide a method for measuring an eddy-current type nonmagnetic metal film thickness which can improve the accuracy of measuring a plate thickness in the case of lift-off, and to provide an apparatus for measuring the same for performing the method.;SOLUTION: The method includes a step of installing an eddy-current measuring sensor 4 on a calibration test piece having the same specifications as those of nonmagnetic metal and selecting the frequency of an exciting current to be supplied to the eddy-current measuring sensor 4 to be a value suitable for each calibration test piece, a step of adjusting the phase angle of the exciting current on the basis of the selected frequency and selecting a phase angle providing smaller rate of fluctuation in the imaginary part output from the eddy-current measuring sensor 4 installed on the calibration test piece, and a step of measuring the film thickness of the nonmagnetic metal on the basis of the frequency and phase angle determined by these steps.;COPYRIGHT: (C)2008,JPO&INPIT